He moves on to face 20th seed Sam Querrey, who is the top-ranked U.S. player here because of Isner's absence. It's the first time Querrey has carried that mantle in a Grand Slam event, but he'd rather not look at things that way.

"I don't feel like I am,'' said Querrey, who dropped a first-set tiebreak to Spanish qualifier Daniel Munoz-De La Nava but played efficiently thereafter and smacked 27 aces in a 6-7 (2), 6-4, 6-2, 6-4 victory. "I feel like the No. 2 American even though John's not here, which is unfortunate. I haven't even thought about it; everyone keeps asking me about it, but it's a complete nonissue.

"I mean, Serena is probably the real leader,'' he added. "I guess on the men's side, a lot of the younger guys are here, so I guess so, a little bit. … I'm just doing the best I can. I'm cheering for the other guys and they're cheering for me, so we're all in it together, but I don't feel like too much of a leader.''

That togetherness will have to be suspended in the second round. Querrey and Baker have gotten to know each other fairly well off the court, but they've played only once before, last year in a Challenger-level tournament on clay where Querrey won in three sets. "We haven't hit too much, so it'll be a little bit of a new scenario,'' Querrey said. "I'm just going to try to keep serving well and dominate with my forehand, and hopefully that's enough to get by him.''..